In the generating cycle of the five seasons in Chinese medicine, it is the Water element that corresponds to the energy of winter. By its nature, Water brings about a descending movement that comes to nourish, lubricate and form a deep reserve in the body.
Traditionally, it is said that Water has its origin in the Kidneys, our energy battery. They are the source of yin and yang, the root of Pre-Heaven and the driving force of all physiological processes. They are where our innate Jing is stored (the vital energy we inherit from our parents), along with the surplus of acquired Jing (the Jing from the air we breathe and from food that the body does not use is stored). Yet, in our daily lives, we tend to use up more Jing, our Essence that safeguards our longevity, than we put in reserve.
The energy of the Kidneys notably governs the bones and produces the marrow. This explains in particular why, in cold and damp weather, pain can appear in the lower back or in the knees. This is called “cold Bi” (Bi Froid), that is, an obstruction of the circulation of Energy and Blood in the energy channels of the back (the Kidney and Bladder meridians), caused by the cold, which is a climatic energy that contracts. When the cold penetrates chronically and settles in the joints, it is then called “Feng Shi Bing”, which can be translated as joint pain or rheumatism.
To take care of our inner source in winter and to prevent lower back and joint pain, it is therefore important not to injure our Yin, by keeping the extremities, the lower back and the knees nice and warm and by limiting how long we are exposed to the cold. It is also better to preserve our Yang, this primordial force that warms us and activates the metabolism and the circulation of the fluids that nourish and lubricate our tendons and our joints. It is advisable, for example, to warm up before starting a winter sports activity and, for people who tend to sweat easily and heavily, to avoid overly strenuous physical effort.
The typical example of a “cold Bi” would be the sudden onset of lower back pain after an intense bout of shovelling done “cold”, with the lower back uncovered..!